//////////////////////////////////////////////////////////////////////////
//
//  Copyright (c) 2021, Cinesite VFX Ltd. All rights reserved.
//
//  Redistribution and use in source and binary forms, with or without
//  modification, are permitted provided that the following conditions are
//  met:
//
//      * Redistributions of source code must retain the above
//        copyright notice, this list of conditions and the following
//        disclaimer.
//
//      * Redistributions in binary form must reproduce the above
//        copyright notice, this list of conditions and the following
//        disclaimer in the documentation and/or other materials provided with
//        the distribution.
//
//      * Neither the name of John Haddon nor the names of
//        any other contributors to this software may be used to endorse or
//        promote products derived from this software without specific prior
//        written permission.
//
//  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
//  IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
//  THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
//  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
//  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
//  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
//  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
//  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
//  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
//  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
//  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
//////////////////////////////////////////////////////////////////////////

#pragma once

#include <boost/noncopyable.hpp>

namespace Gaffer
{
namespace Private
{

/// Assigns a value to something, reassigning the original value when it goes out of scope.
/// T must be copy constructable and assignable
template< typename T >
struct ScopedAssignment : private boost::noncopyable
{
	ScopedAssignment( T& variable, const T& value )
	: m_value( variable )
	, m_variable( variable = value )
	{}

	~ScopedAssignment()
	{
		m_variable = m_value;
	}

private :

	T const m_value;
	T& m_variable;
};

} // Private
} // Gaffer
